.horizontal-navigation {
  /* 添加适当的样式进行布局和样式定制 */
}

.horizontal-navigation ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
}

.horizontal-navigation li {
  margin-right: 10px;
}

.horizontal-navigation a {
  text-decoration: none;
  color: #333;
}

.horizontal-navigation a.active {
  font-weight: bold;
}

.horizontal-navigation .sub-menu {
  display: none;
  position: relative;
  top: 100%;
  left: 0;
  background-color: #fff;
  padding: 10px;
}

.horizontal-navigation li:hover .sub-menu {
  display: block;
}
